U.S. patent application number 11/321121 was filed with the patent office on 2006-09-14 for chip with cleaning cavity.
This patent application is currently assigned to Agilent Technologies, Inc.. Invention is credited to Martin Baeuerle, Thomas Reinhardt.
Application Number | 20060202330 11/321121 |
Document ID | / |
Family ID | 34938951 |
Filed Date | 2006-09-14 |
United States Patent
Application |
20060202330 |
Kind Code |
A1 |
Reinhardt; Thomas ; et
al. |
September 14, 2006 |
Chip with cleaning cavity
Abstract
A chip comprising at least one cleaning cavity adapted for
collecting material when a moveable device is contacted to and
moved relative to the chip.
Inventors: |
Reinhardt; Thomas;
(Karlsruhe, DE) ; Baeuerle; Martin; (Buehlertal,
DE) |
Correspondence
Address: |
Paul D. Greeley;Ohlandt, Greeley, Ruggiero & Perle, L.L.P.
10th Floor
One Landmark Square
Stamford
CT
06901-2682
US
|
Assignee: |
Agilent Technologies, Inc.
|
Family ID: |
34938951 |
Appl. No.: |
11/321121 |
Filed: |
December 29, 2005 |
Current U.S.
Class: |
257/737 ;
257/778; 343/872; 438/106; 438/108 |
Current CPC
Class: |
B01L 2400/0644 20130101;
B01L 3/5027 20130101; F16K 99/0013 20130101; B01L 2400/065
20130101; F16K 99/0001 20130101; F16K 2099/0084 20130101; B01L
2200/141 20130101; B01L 2300/0816 20130101; B01L 13/02 20190801;
F16K 2099/008 20130101; B01L 2300/045 20130101 |
Class at
Publication: |
257/737 ;
257/778; 438/106; 438/108; 343/872 |
International
Class: |
H01L 21/00 20060101
H01L021/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 11, 2005 |
EP |
EP05101909.9 |
Claims
1. A chip comprising at least one cleaning cavity adapted for
collecting material when a moveable device is contacted to and
moved relative to the chip, wherein, in case the chip is a
microfluidic chip with at least one inlet port and at least one
microfluidic channel, each cleaning cavity is fluidically separated
from each inlet port and each microfluidic channel.
2. The chip according to claim 1, wherein the chip is a
microfluidic chip with at least one inlet port and at least one
microfluidic channel, wherein each cleaning cavity is fluidically
separated from each inlet port and each microfluidic channel.
3. The chip according to claim 1, wherein the chip is a cleaning
chip adapted for using within a separation system adapted for
separating compounds of a fluid instead of a microfluidic chip
comprising at least one inlet port and at least one microfluidic
channel.
4. The chip according to claim 1, wherein the cleaning cavity or at
least one of several cleaning cavities comprises at least one of
the following features: the respective cleaning cavity is a through
hole penetrating the chip or a recess open to a contact surface of
the moveable device and not penetrating the chip; the respective
cleaning cavity is formed as a groove or as a slot or has a
circular or oval cross section; the respective cleaning cavity is
manufactured within the chip using laser-cutting or jet-cutting or
die-cutting or injection embossing or etching; the respective
cleaning cavity is provided at a surface of the chip.
5. The chip according to claim 1, comprising at least one of the
following features: the chip is adapted for using within a fluid
separation system adapted for separating compounds of a fluid,
wherein the system is operable in a cleaning mode in which the
moveable device is driven to move a contact surface of the moveable
device into or through at least one position not used in a normal
operation mode of the system in which normal operation mode the
moveable device is driven to control at least one inlet port of a
microfluidic chip comprising the at least one inlet port and at
least one microfluidic channel; the chip is flexible; the chip is
arranged within a frame adapted for inserting the frame together
with the chip into a fluid separation system adapted for separating
compounds of a fluid, wherein the frame preferably comprises at
least one identification-tag, in particular a radio-frequency-chip;
the chip is adapted for interacting with a contact surface of the
moveable device. the material is at least one of dirt, abrasion,
dust.
6. The chip according to claim 1, comprising at least one of the
following features: the moveable device is a valve comprising at
least one moveable or revolving valve element comprising a contact
surface to be cleaned using the chip; the moveable device is a
microfluidic valve, the moveable device is a revolving device. the
chip is adapted for interacting with a contact surface of the
moveable device.
7. A fluid separation system adapted for separating compounds of a
fluid, comprising: a fluid provider adapted for providing the
fluid, a separation unit adapted for separating compounds of the
fluid, a chip according to claim 1, a moveable device adapted for
contacting the chip and adapted for moving relative to the
chip.
8. The system according to claim 7, comprising at least one of the
following features: the moveable device is driven to move a contact
surface of the moveable device into or through at least one
position not used in a normal operation mode of the system in which
normal operation mode the moveable device is driven to control at
least one inlet port of a microfluidic chip comprising the at least
one inlet port; the system is adapted for automatically activating
a cleaning mode when a frame comprising the chip and at least one
identification-tag, in particular a radio-frequency-chip, is
inserted and identified.
9. A method for cleaning a moveable device, comprising the steps
of: contacting the moveable device with a chip having at least one
cleaning cavity, moving the moveable device relative to the chip in
order to clean the moveable device by collecting material in the at
least one cleaning cavity.
10. The method according to claim 9, wherein the movement is
executed as a revolving movement with respect to a revolving axis
in particular extending perpendicular to the contacted
surfaces.
11. A software program or product, preferably stored on a data
carrier, for controlling or executing the method of claim 9, when
run on a data processing system such as a computer.
Description
BACKGROUND ART
[0001] The present invention relates to cleaning of moveable
devices, in particular of valves and/or contacting chips, in
particular microfluidic chips.
[0002] The field of microfluidic laboratory technology comprises
chemical, physical and/or biological analysis, separation or
synthesis of substances on a substrate with a microfluidic
structure. There is a growing demand for such microfluidic
processing systems that has also generated a need for small fluidic
valves. Such miniaturized microfluidic devices have to fulfill a
variety of requirements such as low dead volume and short flow
paths with a cross section as constant as possible. A sufficient
approach in the field is the use of microfluidic chips coupled to
revolving valve elements for flow controlling the microfluidic
processes executed within the chip. One solution for a flexible
microfluidic chip is disclosed for example in the U.S. Pat. No.
5,500,071. One solution for such a revolving valve element is
disclosed for example in EP1520837A1. The teaching of both
documents shall be incorporated herein by reference.
SUMMARY OF INVENTION
[0003] It is an object of the invention to provide an improved
cleaning of such moveable devices. The object is solved by the
independent claims. Preferred embodiments are shown by the
dependent claims.
[0004] According to embodiments of the present invention, the
objects indicated are achieved by a chip comprising at least one
cleaning cavity adapted for collecting material when a moveable
device is contacted to and moved relative to the chip. Therefore,
material accumulated to the moveable device can be removed from the
moveable device by collecting the material in the at least one
cleaning cavity of the chip. The relative movement between the chip
and the moveable device leads to relative positions in which the
material to be removed is positioned within such a cleaning cavity.
This material consequently can fall into the cleaning cavity and is
therefore removed from the moveable device. In addition further
relative movement between the moveable device and the chip forces
the respective material into the cleaning cavity because an edge
surrounding the respective cleaning cavity acts like a wiper and
removes the material from the moveable device such that the removed
material can fall into the cleaning cavity.
[0005] In order to control the microfluidic processes executed
within a microfluidic chip, a revolving valve element can move
relative to the microfluidic chip. During this movement a contact
surface of the revolving valve element is contacted to a surface of
the microfluidic chip. That contact between said surfaces has to be
performed with high quality in order to achieve a sufficient
sealing effect between these contacted surfaces. Such a sealing is
important, since the microfluidic processes operate with high
fluidic pressures and very small volumes; e.g. in the range of
micro-liters or even nano-liters. The advanced cleaning of the
contact surface of the revolving valve element removes disturbing
material. Therefore, grave disturbances of the sealing effect
between the contacted surfaces by material intruding into the
interface between the two contacted surfaces can effectively be
avoided.
[0006] According to embodiments the chip is a microfluidic chip
with at least one inlet port and at least one microfluidic channel,
wherein each cleaning cavity is fluidically separated from each
inlet port and each microfluidic channel. Therefore, the at least
one cleaning cavity is integrated into a microfluidic chip adapted
for executing microfluidic processes. Such a microfluidic chip is
consequently provided with an additional feature, namely the
cleaning of the moveable device.
[0007] According to other embodiments the chip is a cleaning chip
adapted for using within a fluid separation system adapted for
separating compounds of a fluid instead of a microfluidic chip
comprising at least one inlet port and at least one microfluidic
channel. Such a cleaning chip can easily be provided with a special
arrangement of at least one cleaning cavity in order to improve the
cleaning ability of the chip. The arrangement of the at least one
cleaning cavity of such a cleaning chip does not have to consider
ports or other fluidic path elements of a microfluidic chip.
Therefore the cleaning effect of the at least one cleaning cavity
and hence of the chip can be improved.
[0008] Embodiments may also include one or more of the following.
The respective cleaning cavity is a through hole penetrating the
chip or is a recess open to a contact surface of the moveable
device and not penetrating the chip. The respective cleaning cavity
is formed as a groove or as a slot or has a circular or oval cross
section. The respective cleaning cavity is preferably manufactured
within the chip using laser-cutting or jet-cutting. Producing the
cleaning cavity as a through hole is very easy and in particular
suitable for a cleaning chip comprising of only one layer of a
flexible material. On the other hand the production of the cleaning
cavity as a recess is suitable for a microfluidic chip comprising
two or more layers of a flexible material.
[0009] Embodiments further relate to a frame for the chip, wherein
said frame is adapted for positioning the chip within the frame. A
conventional frame is disclosed for example in the International
Patent Application No. EP04/050270 which teaching shall be
incorporated herein by reference.
[0010] Embodiments further relate to a fluid separation system
adapted for separating compounds of a fluid. The system comprises a
fluid provider adapted for providing the fluid, a separation unit
adapted for separating compounds of the fluid, the chip and a
moveable device adapted for contacting the chip and adapted for
providing a relative movement between the moveable device and the
chip. In this system the chip can be used to clean the moveable
device of the system.
[0011] Embodiments further relate to a method for cleaning a
moveable device. The method comprises contacting the moveable
device with a chip having at least one cleaning cavity, and moving
the moveable device relative to the chip in order to clean the
moveable device by collecting material in the at least one cleaning
cavity.
[0012] Other embodiments relate to a software program or to a
software product, which is preferably stored on a data carrier,
controlling or executing the method according to embodiments, when
run on a data processing system such as a computer.
BRIEF DESCRIPTION OF DRAWINGS
[0013] Other objects and many of the attendant advantages of
embodiments of the present invention will be readily appreciated
and become better understood by reference to the following more
detailed description of embodiments in connection with the
accompanied drawings. Features that are substantially or
functionally equal or similar will be referred to by the same
reference signs.
[0014] FIG. 1 depicts a simplified schematic view of a fluid
separation system according to an embodiment of the invention,
[0015] FIG. 2 depicts a perspective view of a frame according to an
embodiment,
[0016] FIG. 3 depicts a perspective view of a chip according to an
embodiment,
[0017] FIG. 4 depicts an enlarged detail IV of the chip of FIG.
3,
[0018] FIG. 5 depicts a perspective view of another chip,
[0019] FIG. 6 depicts an enlarged detail VI of the chip of FIG.
5,
[0020] FIG. 7 depicts an enlarged view of the detail VI of another
embodiment of the chip,
[0021] FIG. 8a to 8c depict simplified and schematic sections of a
chip during cleaning operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] According to FIG. 1 a fluid separation system 1 comprises a
fluid provider 2, a separation unit 3, a chip 4 and a moveable
device 5. The system 1 is adapted for separating compounds of a
fluid, in particular of a liquid. The provider 2 is adapted for
providing the fluid comprising the compounds to be separated. The
provider 2 supplies the fluid to the separation unit 3. In FIG. 1
this fluid supply is depicted using an arrow 6.
[0023] The separation unit 3 is adapted for separating compounds of
the fluid, which is in particular a liquid. The separation unit 3
or the whole system 1 comprises or is a chromatography system, in
particular a liquid chromatography system. Common are for example
high performance liquid chromatography systems (HPLC). HPLC is a
form of chromatography used to separate compounds that are
dissolved in liquid.
[0024] The moveable device 5 is adapted for contacting the chip 4
and is further adapted for providing a relative movement between
the moveable device 5 and the chip 4.
[0025] The chip 4 is preferably arranged within a frame 7.
According to FIG. 2 such a frame 7 is adapted for positioning the
chip 4 within the frame 7. The frame 7 is also adapted for using
within the separation unit 3 of the system 1. The frame 7 may
comprise a grip member 8 simplifying the handling of the frame 7.
The chip 4 or the frame 7 may comprise at least one
identification-tag not shown in the figures. Such an
identification-tag may be e.g. arranged within the grip member 8
and may be a radio-frequency-chip. In case the frame 7 or the chip
4 is provided with such an identification-tag the system 1, in
particular its separation unit 3, is preferably provided with a tag
reader 9 adapted for providing one-way or bilateral data
transmission between the identification-tag and the tag reader 9.
According to FIG. 1 the frame 7 is positioned within the separation
unit 3 using the movable device 5 and a connector 30 coupled to the
fluid supply 6 of the provider 2.
[0026] According to an embodiment of the present invention shown in
FIG. 3 the chip 4 may be designed as a microfluidic chip 10
comprising at least one inlet port 11 (see FIG. 4) and at least one
microfluidic channel 12. The microfluidic channel 12 depicted in
FIG. 3 may be, for example, a separation column of a liquid
chromatography system.
[0027] In the shown embodiment the chip 4 comprises at least two
positioning openings 13. The separation unit 3 is provided with
positioning pins (not shown) adapted for interacting with the
positioning openings 13 in order to provide proper alignment of the
chip 4 relative to the moveable device 5, when the frame 7 together
with the chip 4 is inserted into the separation unit 3.
[0028] According to FIG. 4 the microfluidic chip 10 may comprise an
arrangement of several ports. In this embodiment exist six ports,
namely the at least one inlet port 11 and five other ports 14. Each
of this other ports 14 may be designed as one of a through hole and
an inlet port connected to a flow path within the microfluidic chip
10. The microfluidic channel 12 is such a flow path.
[0029] The chip 4 is provided with a least one cleaning cavity 15.
FIG. 4 shows an example of a chip 4 having eight cleaning cavities
15. In the example of FIG. 6 the chip 4 is also provided with eight
cleaning cavities. But in the example according to FIG. 7 the chip
4 has only one cleaning cavity 15. The number and arrangement of
cleaning cavities 15 is not limited to the examples of the shown
embodiments. Also the form and shape of the cleaning cavities 15 is
not limited to the examples shown in the figures. As depicted in
the FIGS. 4, 6 and 7 each cleaning cavity 15 is formed as a groove
or as a slot. It should be clear, that in other embodiments the at
least one cleaning cavity 15 may also have a circular or an oval
cross section. The cleaning cavities 15 may be provided using
laser-cutting or jet-cutting the chip 4. With help of such
manufacturing methods the cleaning cavities 15 may be provided with
tiny dimensions. This may be appropriate with respect to a chip 4
designed as a microfluidic chip 10, because the cleaning cavities
have to be arranged nearby the ports 11 or 14, respectively.
Basically it is also possible to realize the cleaning cavities 15
by die-cutting or by injection embossing or by etching.
[0030] Since the chip 4 is designed as a microfluidic chip 10 each
cleaning cavity 15 is fluidically separated from each port 11, 14
and therefore also from each microfluidic channel 12 of the
microfluidic chip 10. The object of this separation is to avoid
leakage within the arrangement of the chip 4 interacting with the
moveable device 5.
[0031] Preferably the moveable device 5 is designed as revolving
device 5'. Such a revolving device 5' is adapted for providing a
rotating movement between the chip 4 and the revolving device 5' or
a revolving member of the revolving device 5'. In a preferred
embodiment the revolving device 5' comprises a revolving element
(not shown) adapted for interacting with the chip 4. In particular
the revolving device 5' is designed as a microfluidic valve 5''
comprising in particular a revolving valve element (not shown). The
moveable device 5 or the revolving device 5' or the microfluidic
valve 5'', respectively, comprises a contact surface 22 (see FIG.
8a-8c) adapted for interacting with the chip 4. The contact surface
22 is preferably provided at the respective revolving element, or
the revolving valve element, respectively.
[0032] According to FIGS. 3 and 4 the chip 4 comprises a surface 16
adapted for interacting with the contact surface 22 of the moveable
device 5 or the revolving device 5' or the microfluidic valve 5'',
respectively. In use of the chip 4 the contact surface 22 and the
surface 16 are contacted together and form an interface 23 (see
FIG. 8a-8c) between that surfaces 16, 22.
[0033] The contact surface 22 is adapted for controlling the ports
11 and 14 of the microfluidic chip 10. This controlling is achieved
by adjusting the relative position between the moveable device 5
and the chip 4. To this end the contact surface 22 may be provided,
for example, with a least one fluid conducting feature (not shown)
adapted for providing a fluid connecting between at least two ports
11, 14 depending on the relative position between the moveable
device 5 and the chip 4. For detailed explanation of such a
microfluidic valve 5'' see for example the aforementioned
EP1520837A1.
[0034] Since the moveable device 5 is a revolving device 5' or a
microfluidic valve 5'', respectively, a revolving axis 17 (see
FIGS. 4, 6, 7) defines the rotary movement between the rotary
device 5' and the chip 4. The revolving axis 15 stands on the
drawing plane of the FIGS. 4, 6 and 7, and in particular extends
perpendicular to the surfaces 16, 22.
[0035] The rotary movement between the contacted surfaces 16, 22
defines cleaning zones 18 on the contact surface 22 of the moveable
device 5. In the FIGS. 4, 6 and 7 the cleaning zones 18 are limited
using dash lines. The cleaning zones 18 are defined by the shape of
the cleaning cavities 15 in combination with the relative movement
between the surface 16 provided with the cleaning cavities 15 and
the contact surface 22 to be cleaned.
[0036] In the embodiment of FIG. 4 the cleaning cavities 15 define
two radially separated cleaning zones 18. Each cleaning zone 18
having the form of an annulus. Radially between the two cleaning
zones 18 is defined an intermediate zone 19 also in form of an
annulus. The ports 11 and 14 are arranged within this intermediate
zone 19.
[0037] In another embodiment according to FIG. 5 the chip 4 can be
designed as a cleaning chip 20. Such a cleaning chip 20 is also
provided at its surface 16 with at least one cleaning cavity 15. A
difference between the cleaning chip 20 and the microfluidic chip
10 is that the cleaning chip 20 is not adapted for executing
microfluidic processes within the chip 4. Therefore, the cleaning
chip 20 does not comprise at least one of a microfluidic channel 12
and an inlet port 11. According to this, the arrangement of the
cleaning cavities 1 does not depend on the positions of ports 11,
14 within the surface 16 of the chip 4. Consequently the cleaning
ability of the cleaning chip 20 can be improved by adapting the
arrangement of cleaning cavities 15 with respect to at least one of
the number of the cleaning cavities 15, the geometric shape of the
cleaning cavities 15 and the dimensions of the cleaning cavities
15.
[0038] FIGS. 6 and 7 show two preferred examples of such cleaning
cavity arrangements. According to FIG. 6 the cleaning cavity
arrangement comprises eight cleaning cavities 15 having a star like
arrangement with respect to the revolving axis 17 of the rotary
movement between the revolving device 5' or the microfluidic valve
5'', respectively, and the chip 4. This cleaning cavities 5 define
a single cleaning zone 18 also having the shape of an annulus.
Compared to the cleaning zones 18 of the example shown in FIG. 4
the singly cleaning zone 18 according to the embodiment of FIG. 6
covers an area which is significantly larger than the area covered
by the two cleaning zones 18 of the embodiment according to FIG.
4.
[0039] According to FIG. 7 the surface 16 of the cleaning chip 20
comprises in another embodiment only one cleaning cavity 15
designed as a groove or slot. The dimensions of this cleaning
cavity 15 can simply be adapted for cleaning the whole contact
surface of the revolving device 5'. It is clear, that the two
embodiments of the FIGS. 6 and 7 are only examples not limiting the
scope of the invention.
[0040] The cleaning principle of the chip 4 according to
embodiments of the invention is explained in the following with
respect to the FIGS. 8a to 8c.
[0041] The FIGS. 8a to 8c show schematically the interaction of the
chip 4, which can be designed e.g. as a microfluidic chip 10 or as
a cleaning chip 20, and the moveable device 5, which can be
designed e.g. as a revolving device 5' or as microfluidic valve
5''. In the depicted example chip 4 is a multi-layer chip 4
comprising three layers 21 of a flexible material, in particular
plastics or synthetics. Preferably, a microfluidic chip 10 is
designed as a multi-layer chip. On the other hand a cleaning chip
20 is preferably designed as a single-layer chip. Therefore, the
cleaning chip 20 has reduced manufacturing costs and may be
designed as a product for one-time-usage. The portion of the
moveable device 5 depicted in the FIGS. 8a to 8c typically is a
moveable or revolving element, in particular a revolving valve
element, of the moveable device 5, said element is provided with
the contact surface 22. The chip 4, in particular the microfluidic
chip 10 or the cleaning chip 20, respectively, is made of a
flexible material having a hardness which is preferably as high as
possible but smaller than the hardness of the contact surface 22 in
order to avoid damage of the contact surface 22.
[0042] FIG. 8a shows a normal operation condition in which the
contact surface 22 of the moveable device 5 contacts the surface 16
of the chip 4. The surface 16 and the contact surface 22 preferably
are even or plane. Thus, the surfaces 16, 22 have a
two-dimensional-contact and define an interface 23 between each
other. Usually, the chip 4 and the moveable device 5 are pressed
together in order to achieve a suitable sealing effect within the
interface 23. That pressure is symbolized by arrows 24.
[0043] If the contact surface 22 of the moveable device 5 is clean,
a high quality contact between the surfaces 16, 22 can be
established. The sealing effect within the interface 23 depends on
the quality of the contact between the surfaces 16, 22.
[0044] In a normal operation mode of the system 1 the moveable
device 5 can be moved or is driven to move its contact surface 22
relative to the chip 4. This relative movement is symbolized by an
arrow 25. According to different functions of the microfluidic chip
10 the moveable device 5 is adapted to adjust the contact surface
22 into at least one, preferably several, positions in order to
control the at least one input port 11, and in particular also the
other ports 14, of the microfluidic chip 10. During this normal
operation mode an effective sealing in the interface 23 can be very
important in order to achieve a high quality performance of the
system 1.
[0045] FIG. 8b shows an operation condition in which the contact
surface 22 of the moveable device 5 is contaminated with material
26. That material 26 may be, for example, dirt, abrasion or dust or
a combination thereof. In operation of the system 1 the material 26
may be disposed between the surfaces 16 and 22 and therefore
disturbs the contact between that surfaces 16, 22. In the condition
shown in FIG. 8b the material 26 causes a gap 27 within the
interface 23. The gap 27 between the surfaces 16, 22 affects the
sealing and results in leakage symbolized by an arrow 28. In order
to achieve high quality performance of the system 1 leakage within
the interface 23 has to be avoided.
[0046] According to embodiments of the invention the chip 4 is
provided with at least one cleaning cavity 15. The section depicted
in the FIGS. 8a to 8c shows a portion of the chip 4 provided with
one of such cleaning cavities 15. As a result of the relative
movement between the chip 4 and the moveable device 5 the material
26 is moved relative to the cleaning cavity 15. Consequently, the
contact surface 22 contaminated with the material 26 arrives a
relative position according to FIG. 8c in which the material 26
faces the cleaning cavity 15. Thus, the material 26 can fall into
the cleaning cavity 15. Additionally, further movement 25 of the
contact surface 22 results in a wiping effect of an edge 29 of the
cleaning cavity 15. That edge 29 encloses the cleaning cavity 15.
The wiping or cleaning effect of the edge 29 is intensified using
the pressure 24 forcing the two surfaces 16, 22 together.
[0047] Each cleaning cavity 15 is adapted to collect the material
26. This adaptation is achieved for example, using at least one of
said edge 29 and appropriate dimensions of the profile of the
cleaning cavity 15.
[0048] After the material 26 has entered the cleaning cavity 15
according to FIG. 8c the material 26 remains within the cleaning
cavity 15 even if further relative movement between the surfaces
16, 22 occurs. Therefore, the cleaning cavity 15 collects the
material 26. Even if the material 26 adheres at the contact surface
22 the material 26 remains within the cleaning cavity 15. This is
because the material 26 loosens and falls into the cleaning cavity
15, as a result of the further movement between the surfaces 16,
22.
[0049] In the example of the FIGS. 8a to 8c the cleaning cavity 15
is designed as a recess which is open to the contact surface 22 and
which does not penetrate the chip 4. In another embodiment the
cleaning cavity 15 may also be designed as a through hole
penetrating the chip 4.
[0050] In order to clean the contact surface 22 of the moveable
device 5 the system 1 preferably is operable in a cleaning mode. In
said cleaning mode the system 1 or a controller (not shown) of the
system 1 drives or actuates the moveable device 5 to move its
contact surface 22 into or through at least one position which is
not used in the normal operation mode, mentioned above, of the
system. For example, in the normal operation mode the moveable
device 5 performs a switching movement between two predetermined
relative positions. In case of a revolving movement the rotation
lies within a range of less than 360.degree., for example
60.degree.. In the cleaning mode said controller drives the
moveable device 5 such that the contact surface 22 arrives relative
positions exceeding the range of predetermined movement of the
normal operation mode. In the example mentioned above the moveable
device 5 adjusts the contact surface 22 preferably for a full turn
of 360.degree. or more.
[0051] According to a preferred embodiment the frame 7 is provided
with the chip 4, which is designed as a cleaning chip 20. The frame
7 also comprises an identification-tag, in particular a
radio-frequency-chip, mentioned above. Under normal conditions the
system 1 operates with a conventional microfluidic chip 10
comprising at least one inlet port 11 and at least one microfluidic
channel 12. This conventional microfluidic chip 10 is not provided
with any cleaning cavity 15. Preferably such a microfluidic chip 10
is positioned within a frame 7 and is inserted into the separation
unit 3 together with the frame 7.
[0052] In order to clean the moveable device 5 the conventional
microfluidic chip 10 has to be replaced by the chip 4, in
particular by the cleaning chip 10. The cleaning chip 10 is
inserted into the separation unit 3 together with its frame 7 which
is provided with said identification-tag. After inserting the frame
7 with the cleaning 10 into the separation unit 3 the tag-reader 9
and the identification-tag start communication and transfer data. A
controller (not shown) coupled to the tag-reader 9 is adapted for
automatically start the cleaning mode of the system 1 when the
cleaning chip 10 is inserted into the separation unit 3.
[0053] In order to implement this feature into the controller of
the separation unit 3 said controller is provided with a software
program. That software program is adapted for controlling or
executing the cleaning method according to embodiments of the
invention. That controller therefore comprises or is designed as a
data processing system such as a computer.
* * * * *